Federal authorities are asking Virginia Gov. Robert F. McDonnell’s associates about previously undisclosed gifts given by a campaign donor to McDonnell’s wife that total tens of thousands of dollars and include money and expensive designer clothing, according to people familiar with the inquiry.

The questions are part of broad federal and state investigations into gifts to the governor and his family and whether McDonnell (R) took official action on behalf of anyone who gave gifts, people with knowledge of the investigation have said.

The probe already involves a $15,000 gift from wealthy businessman Jonnie R. Williams Sr., chief executive of a major McDonnell campaign donor, for catering at the 2011 wedding of one of McDonnell’s daughters.

But the people with knowledge of the inquiry, who spoke on the condition of anonymity because of the sensitive nature of the investigation, say the scope is wider than just the wedding gift. The value and nature of additional gifts from Williams, including money provided in several checks, suggest that authorities are exploring a more extensive relationship between Williams and the McDonnells than previously revealed.

McDonnell has said that Williams’s company, Star Scientific Inc., the maker of a dietary supplement, received no special benefits. But the gifts came as the McDonnells showcased the company and its new product.

Additionally, famed Virginia socialite Patricia Kluge, who was one of the state’s wealthiest women before a dramatic and public crash during the recession, has been subpoenaed to appear before a grand jury to answer questions related to the McDonnells, according to people who are familiar with her summons.

It is not clear what testimony authorities will seek from Kluge, who owned a winery and vast estate near Charlottesville before losing both in the economic downturn.

Kluge’s attorney, Edward B. MacMahon Jr., said his client has done nothing wrong. “Patricia Kluge is a close friend of Mrs. McDonnell’s,” MacMahon said. “The government is apparently looking into lots of Mrs. McDonnell’s friends, but any insinuation that Kluge has any knowledge of anything illegal or improper done by either the governor or the First Lady is entirely wrong.’’

A spokesman for the U.S. attorney’s office declined to comment.

Tucker Martin, a spokesman for the governor, said “we will not address personal matters that are not relevant or germane to Virginia state government functions.”

But in a written statement, Martin also said that the governor has been “diligent in following Virginia’s existing laws regarding the reporting of gifts to state officeholders.”

He added that neither Williams nor Star Scientific have received any targeted tax incentives, economic-development grants, government contracts or board appointments during McDonnell’s time in office.

Jerry Kilgore, an attorney for Williams, declined to comment on the federal investigation.

Virginia law allows elected officials to accept gifts of any value, provided that they annually disclose those worth more than $50.

Since taking office in 2010, McDonnell has disclosed receiving $9,650 in personal gifts — including private plane rides and a summer lake-house vacation — from Williams and Star Scientific.

Star Scientific also contributed $108,452 to McDonnell’s campaign and his political-action committee.

State law does not require officials to disclose gifts that have been given to members of their immediate family. McDonnell has said that is why he did not disclose the $15,000 check for his daughter’s wedding, which he said was a gift to his daughter.

As public scrutiny of his relationship with Williams has mounted, McDonnell has declined to provide a full accounting of other gifts Williams provided to members of the McDonnell family.

A local prosecutor in Richmond is conducting a parallel investigation to the federal probe to determine whether McDonnell complied with state law in his annual financial filings.

That investigation could explore whether the governor received enough benefit from gifts given to his wife — particularly loans or gifts of money — that he should have considered them gifts to himself as well.

Federal authorities are exploring whether McDonnell performed official acts to boost the company in exchange for gifts from Williams, people familiar with the inquiry have said.

Three days before the 2011 wedding, Maureen McDonnell flew to Florida, where she touted the promise of a dietary supplement that Star Scientific was introducing to doctors and investors.

Three months later, the McDonnells allowed Star Scientific to use the 200-year-old Executive Mansion for an event to mark the launch of Anatabloc, which is an anti-inflammatory, non-FDA approved pill.

The first lady organized the event, but the governor also attended. His spokesman has said he stopped in to recognize the company for making grants to public universities.

The federal probe appears not to be limited to the McDonnells’ interactions with Williams.

State Del. David I. Ramadan (R-Loudoun), who confirmed this month that he has been subpoenaed to appear before the grand jury next month, has said he has no connection to Williams or his company.

Ramadan, who is a jeweler, has declined to say whether he gave gifts to Maureen McDonnell.

Kluge, too, has no obvious connection to Star Scientific.

She has been active politically in Virginia but has given largely to Democrats, including more than $125,000 to Sen. Timothy M. Kaine’s gubernatorial campaign and inauguration. In 2010, however, she gave a $10,000 campaign contribution to McDonnell’s Inaugural Committee.

Friendly with the McDonnells, she served for 18 months in 2010 and 2011 as chairwoman of the Citizens’ Advisory Committee for Furnishing and Interpreting the Executive Mansion, a panel appointed by the governor and whose honorary head is the first lady.

For two decades, Kluge reigned as a particular kind of Virginia royalty, entertaining high society at her 45-room, 23,000-square-foot estate not far from Thomas Jefferson’s Monticello, outside of Charlottesville.

She had built the mansion with billionaire husband John Kluge, who was the nation’s wealthiest person during their marriage. Patricia Kluge kept the home after they divorced in 1990.

She later built a winery on 900 acres that was the crown jewel of the burgeoning Virginia wine industry. But her debts mounted amid the financial crash, and she declared bankruptcy in 2011.

Trump, a longtime friend, purchased Kluge’s holdings from trusts and banks, buying the winery in 2011 and her famed Albemarle House a year later.

Martin, the governor’s spokesman, said that before the sale at public auction, Secretary of Agriculture Todd Haymore had worked to identify potential buyers.

Martin said all efforts to save the enterprise were coordinated by Haymore, who had also worked with Kluge during the Kaine administration. He said it was in the best interest of the state to find a buyer.

“While Mrs. Kluge is a friend of the McDonnells, the Kluge Vineyard was Virginia’s largest and thus had a direct impact on the growing Virginia wine industry,” Martin said.

Eric Trump, who oversaw the purchase of the winery for the Trump Organization, said in an interview that while the McDonnells were supportive of the Trump takeover, they had no personal role in the deal.

“The governor, obviously, I think he’s probably a big proponent of ours — as would be any governor,” Trump said. But, he added, “the governor didn’t have a role in the sale.”

Trump said he has not been subpoenaed to appear at the grand jury or been interviewed by the FBI.